Objective
To evaluate the rate of change in serum lipids and the factors associated with their variations, stratifying for pre‐pregnancy body mass index (BMI) categories.
Design
Prospective cohort.
...Setting
Public Health centre, Rio de Janeiro, Brazil.
Population
Two hundred and twenty‐five healthy pregnant women recruited between 2009 and 2011.
Methods
Women were evaluated during the three trimesters of pregnancy (5th–13th, 20th–26th and 30th–36th gestational weeks). Pre‐pregnancy BMI (kg/m²) was classified as normal weight (NW = 18.5–24.9), overweight (OW = 25.0–29.9) or obese (OB ≥ 30.0). The independent variables included maternal socioeconomic, demographic, biochemical and lifestyle factors. We performed linear mixed‐effects models adjusted for gestational age and body weight, reporting coefficient (β) and 95% confidence interval (95% CI).
Main outcome measures
Longitudinal total cholesterol (TC), high‐density lipoprotein (HDL‐c), low‐density lipoprotein (LDL‐c) and triglyceride (TG) measurements.
Results
OW and OB women presented higher mean TG, TC and LDL‐c compared with their NW counterparts (P < 0.05). The mean HDL‐c concentrations were higher in NW than in OB women (P = 0.03). OW and OB women presented lower serum TC (βOW = −0.014; 95% CI = −0.026 to −0.002; P = 0.022; βOB = −0.015; 95% CI −0.015 to 0.001; P = 0.066) and LDL‐c (βOW = −0.012; 95% CI = −0.021 to −0.002; P = 0.017; βOB = −0.018; 95% CI = −0.031 to −0.005; P = 0.005) rates of change (mmol/l per gestational week) compared with the NW. Pre‐gestational BMI was the main factor associated with the rate of changes in TC and LDL‐c concentrations.
Conclusion
Pre‐pregnancy BMI was the main factor associated with the rate of change in TC and LDL‐c throughout pregnancy, and OW and OB women presented lower rates of change compared with NW controls.
Agricultural field experiments are costly and time-consuming, and often struggling to capture spatial and temporal variability. Mechanistic crop growth models offer a solution to understand intricate ...crop-soil-weather system, aiding farm-level management decisions throughout the growing season. The objective of this study was to calibrate and the Crop Environment Resource Synthesis CERES-Maize (DSSAT v 4.8) model to simulate crop growth, yield, and nitrogen dynamics in a long-term conservation agriculture (CA) based maize system. The model was also used to investigate the relationship between, temperature, nitrate and ammoniacal concentration in soil, and nitrogen uptake by the crop. Additionally, the study explored the impact of contrasting tillage practices and fertilizer nitrogen management options on maize yields. Using field data from 2019 and 2020, the DSSAT-CERES-Maize model was calibrated for plant growth stages, leaf area index-LAI, biomass, and yield. Data from 2021 were used to evaluate the model's performance. The treatments consisted of four nitrogen management options, viz., N0 (without nitrogen), N150 (150 kg N/ha through urea), GS (Green seeker-based urea application) and USG (urea super granules @150kg N/ha) in two contrasting tillage systems, i.e., CA-based zero tillage-ZT and conventional tillage-CT. The model accurately simulated maize cultivar's anthesis and physiological maturity, with observed value falling within 5% of the model's predictions range. LAI predictions by the model aligned well with measured values (RMSE 0.57 and nRMSE 10.33%), with a 14.6% prediction error at 60 days. The simulated grain yields generally matched with measured values (with prediction error ranging from 0 to 3%), except for plots without nitrogen application, where the model overestimated yields by 9-16%. The study also demonstrated the model's ability to accurately capture soil nitrate-N levels (RMSE 12.63 kg/ha and nRMSE 12.84%). The study concludes that the DSSAT-CERES-Maize model accurately assessed the impacts of tillage and nitrogen management practices on maize crop's growth, yield, and soil nitrogen dynamics. By providing reliable simulations during the growing season, this modelling approach can facilitate better planning and more efficient resource management. Future research should focus on expanding the model's capabilities and improving its predictions further.
Cropping practice (tillage) is an important management tool for tackling water induced erosion hazard, promoting in situ water conservation and improving and stabilising crop yields from rainfed ...production systems of semiarid and subtropical regions. Four practices including conventional tillage (CT), ridge farming tillage (RFT), no tillage (NT) and stubble mulch farming tillage (SMFT) were evaluated for 11 years (1990-1991 to 2001-2002) under semiarid rainfed conditions in western India on a very deep, sandy loam soil. Green gram super(1) (Vigna radiata)-mustard (Brassica juncea) sequential cropping and pearl millet (Pennisetum glaucum) + pigeon pea (Cajanus cajan) intercropping systems were tested for the first four years (first phase of the experiment). Cowpea (Vigna unguiculata)-mustard sequential cropping and cowpea + castor (Ricinus communis) intercropping systems were used for the following seven years (second phase of the experiment). Runoff, soil losses, sediment concentrations, crop yields, soil organic carbon, bulk density and water stable aggregates were observed for all the treatment combinations. RFT and SMFT were both effective in reducing runoff and soil loss. RFT, NT and SMFT reduced runoff by 69.4, 16.2 and 59.6% respectively compared with CT. Average soil loss in NT was 37.2% less than CT. Average sediment concentration of runoff during June-July was greater than in August-October for all treatments and average sediment concentrations were greater under CT and RFT. The highest average yield of all crops except green gram was recorded under SMFT. Surface soil organic carbon (SOC), bulk density and water stable macro-aggregates were all significantly greater under NT at the end of the experiment, but reverting to uniform tillage negated this effect. Micro-aggregates built-up under SMFT were relatively more stable than those all under NT. The results of this study demonstrate that in the semi-arid sub-tropical agro-ecosystem of Gujarat (western India) adoption of SMFT can significantly improve and stabilise the crop yields and reverse land degradation process.
Propagation of an electron wave packet through a quantum point contact (QPC) defined by electrostatic gates in bilayer graphene is investigated. The gates provide a bias between the layers, in order ...to produce an energy gap. If the gates on both sides of the contact produce the same bias, steps in the electron transmission probability are observed, as in the usual QPC. However, if the bias is inverted on one of the sides of the QPC, only electrons belonging to one of the Dirac valleys are allowed to pass, which provides a very efficient valley filtering.
Identifying suitable zones for surface water storage and groundwater recharge is needed to enhance irrigation water availability. This study was undertaken to map rainwater harvesting (RWH) potential ...zones using geospatial tools and analytic hierarchy process (AHP). The suitable locations for RWH were also mapped using the Boolean logic concept. The surface runoff is a vital factor to demarcate the appropriate zones for RWH. The curve number approach was used to estimate the surface runoff potential. The runoff coefficient (RC) map was generated based on rainfall and surface runoff depth. Weights have been allocated to selected themes of RC, drainage density, and slope. The themes were integrated using geographic information system (GIS) and AHP to demarcate the suitable zones for RWH. The derived RWH potential map was categorized into zones like “very good,” “good,” “moderate,” “poor,” and “very poor” with an aerial extent of 14.3%, 24.7%, 28.3%, 20.2%, and 12.6%, respectively. The area suitable for farm ponds was found to be about 9% (408 km
2
), 13% (329 km
2
), and 4% (244 km
2
) in Mirzapur, Chandauli, and Sonbhadra districts, respectively. Furthermore, 22, 15, and 21 locations were found suitable for check dams in Mirzapur, Chandauli, and Sonbhadra districts, respectively. At a large scale, effective planning of water management strategies based on multicriteria decision analysis and GIS offers increased availability of surface and groundwater resources and may help for enhancing the agricultural land use options. The higher resolution maps may be further utilized to plan RWH strategies at village level.
Reference evapotranspiration (ET
0
) is one of the crucial variables used for irrigation scheduling, agricultural production, and water balance studies. This study compares six different models with ...sequential inclusion of six meteorological input variables such as minimum temperature (Tmin), maximum temperature (Tmax), mean relative humidity (RH), wind speed (SW), sunshine hours (HSS), and solar radiation (RS), which are necessarily used in physical or empirical-based models to estimate ET
0
. Each model utilized three variants of machine learning algorithms, i.e. Additive Regression (A
d
R), Random Subspace (RSS), M5 Pruning tree (M5P) independently and four novel permutated hybrid combinations of these algorithms. To evaluate the efficacy of these hybridizations and the stability of machine learning models, a comprehensive evaluation of independent and hybrid models was performed. With more input variables, the model performances were found to be superior in terms of prediction accuracies. The model A
d
R6 that included all the 6 selected meteorological variables outperformed other models during the testing period, exhibiting statistical performance of MAPE (1.30), RMSE (0.07), RAE (2.41), RRSE (3.10), and R
2
(0.998). However, the A
d
R algorithm, alone, was found to capture about 86% of variance in the observed data conforming to the 95% confidence band across all models irrespective of the number of input variables used to predict ET
0
. The RSS algorithm, in comparison to other algorithms, failed to capture the observed trends even with all the input variables. The hybrid combinations of algorithms with A
d
R as a constituent were better performers in terms of their prediction accuracies but remained inferior to A
d
R as an individual performer. All the algorithms are better predictors of the higher values of ET
0
that included values beyond the 75% quartile.
Bone growth and repair are under the control of biochemical and mechanical signals. Low-intensity pulsed ultrasound (LIPUS) stimulation at 30
mW/cm
2 is an established, widely used and FDA approved ...intervention for accelerating bone healing in fractures and non-unions. Although this LIPUS signal accelerates mineralization and bone regeneration, the actual intensity experienced by the cells at the target site might be lower, due to the possible attenuation caused by the overlying soft tissue. The aim of this study was to investigate whether LIPUS intensities below 30
mW/cm
2 are able to provoke phenotypic responses in bone cells. Rat bone marrow stromal cells were cultured under defined conditions and the effect of 2, 15, 30
mW/cm
2 and sham treatments were studied at early (cell activation), middle (differentiation into osteogenic cells) and late (biological mineralization) stages of osteogenic differentiation. We observed that not only 30
mW/cm
2 but also 2 and 15
mW/cm
2, modulated ERK1/2 and p38 intracellular signaling pathways as compared to the sham treatment. After 5
days with daily treatments of 2, 15 and 30
mW/cm
2, alkaline phosphatase activity, an early indicator of osteoblast differentiation, increased by 79%, 147% and 209%, respectively, compared to sham, indicating that various intensities of LIPUS were able to initiate osteogenic differentiation. While all LIPUS treatments showed higher mineralization, interestingly, the highest increase of 225% was observed in cells treated with 2
mW/cm
2. As the intensity increased to 15 and 30
mW/cm
2, the increase in the level of mineralization dropped to 120% and 82%. Our data show that LIPUS intensities lower than the current clinical standard have a positive effect on osteogenic differentiation of rat bone marrow stromal cells. Although Exogen™ at 30
mW/cm
2 continues to be effective and should be used as a clinical therapy for fracture healing, if confirmed
in vivo, the increased mineralization at lower intensities might be the first step towards redefining the most effective LIPUS intensity for clinical use.
Groundwater recharge from water storage structures under semi-arid conditions of western India has been estimated by employing water table fluctuation (WTF) and chloride mass balance (CMB) methods. ...Groundwater recharge was estimated as 7.3% and 9.7% of the annual rainfall by WTF method for the years 2003 and 2004, respectively while the two years average recharge was estimated as 7.5% using CMB method. A Recharge function depicting the relationship between potential recharge from storage structures and successive day averaged storage depths was better exhibited by a power function. A diagnostic relationship correlating the rainfall to the potential recharge from water storage structures has been developed to explain the characteristics of the storage structures for a given geographical location. The study has revealed that a minimum of 104.3
mm cumulative rainfall is required to generate 1
mm of recharge from the water storage structures. It was also inferred that the storage structures have limited capacity to induce maximum recharge irrespective of the amount of rainfall and maximum recharge to rainfall ratio is achieved at a lower rainfall than the average annual rainfall of the area. An empirical linear relationship was found to reasonably correlate the changes in chloride concentration with water table rise or fall in the study area.
Only since the late 1980s have lizard specialists begun incorporating phylogenetic information to the classification of leiosaurids. These are among the most enigmatic South American lizards, with 35 ...currently recognised species arranged in six genera. To evaluate their relationships, we assembled a data set based on published and novel information containing 135 morphological characters and 11,235 DNA base pairs (14 loci) for up to 52 terminals, including outgroups. We performed 13 analyses based on different optimality criteria (parsimony, maximum likelihood, and coalescent approach) and indel coding strategies (gaps coded as missing data or as a fifth state). We also evaluated the impact of phenotypic evidence on the phylogeny of leiosaurids, and investigated the level of informativeness and potential sources of topological conflict using a Quartet Sampling analysis. Phylogenetic analyses supported the monophyly of major leiosaurid clades, including subfamilies Enyaliinae and Leiosaurinae, and the 'para-anoles' clade (Urostrophus + Anisolepis). However, Urostrophus was inferred as paraphyletic, with U. vautieri forming a clade with Anisolepis. These relationships motivate the synonymization of Anisolepis Boulenger,
1885
with Urostrophus Duméril & Bibron, 1837. The monophyly of Pristidactylus and, surprisingly, of Enyalius, were also challenged, underscoring the need for additional phylogenetic work. Finally, we described Urostrophus chungarae sp. nov. from the Torotoro National Park, Potosí, Bolivia. This apparently rare leiosaurid was inferred as sister to U. gallardoi, a Chacoan species distributed in northern Argentina and southeastern Bolivia. We conclude with a revised classification of Leiosauridae and by pointing out a number of unresolved issues that require further systematic investigation.
http://www.zoobank.org/urn:lsid:zoobank.org:pub:F60EB6CB-62B2-4EE3-B1A8-BEE3B2ED7A65
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